Minidsp Flex Review (Audio DSP)

[Red_Red]

I changed my mind and don't want to get the minidsp anymore. It's just too expensive in the EU for the feautures it has.
A Topping DM7 with a Raspberry Pi or PC can do more powerful DSP things, has 8 channels and is 150€ less expensive. I hope they'll come up with a 4 or 6 channel version of the DM7 for even less money

Going by experience I would say to my past "me" that buying the right equipment at an early stage might seem a big sum if money, but it is less than buying a product and upgrading over time. .....I have lots of dacs to sell...note to self: sell them.

My advice to you based on the above is to buy the minidsp with the future use of subs in mind.

Not to mention the price of the cables (rca to XLR), and the time to install the multiple programs on the RPi, etc. The advantage of the Flex Eight is clearly its integration. also having spdif inputs and bluetooth in addition to the usb is a plus for example to connect it directly to the TV and / or an external audio player or a smartphone in addition to a computer.

For my part, with a Nanodigi, I was thinking of getting three Topping E30s in addition to the one I already have to improve my active crossover. But when you calculate everything, including taking into account the price of the cables and the ugly "octopus" aesthetics of their number, the choice is quickly made. The Flex Eight is obviously a winner.

On the other hand, it is clear that the price charged (for now) in Europe is excessive. At 800 euros it would be more suitable. But at 1000 euros for example on Audiophonics, it is even better to order it directly from the minidsp shop, even if it means losing the 2-year European guarantee.

But maybe before taking the plunge, it would be wiser to wait for Amir to do the full review. Even if Minidsp demonstrated with the previous Flex, their ability to do things correctly.

 

[juliangst]

Not to mention the price of the cables (rca to XLR), and the time to install the multiple programs on the RPi, etc. The advantage of the Flex Eight is clearly its integration. also having spdif inputs and bluetooth in addition to the usb is a plus for example to connect it directly to the TV and / or an external audio player or a smartphone in addition to a computer.

For my part, with a Nanodigi, I was thinking of getting three Topping E30s in addition to the one I already have to improve my active crossover. But when you calculate everything, including taking into account the price of the cables and the ugly "octopus" aesthetics of their number, the choice is quickly made. The Flex Eight is obviously a winner.

On the other hand, it is clear that the price charged (for now) in Europe is excessive. At 800 euros it would be more suitable. But at 1000 euros for example on Audiophonics, it is even better to order it directly from the minidsp shop, even if it means losing the 2-year European guarantee.

It's actually easier than you think.
You just have to install MoOde or Volumio on the Pi which both come with CamillaDSP build into it.

If you need an optical input you can simply buy a HifimeDIY optical to USB adapter (about 30€) and select input the input source in MoOde.
You can do all the DSP,PEQ and convoution stuff inside camillaDSP and I didn't have any issues running it under MoOde so far (I only used it in stereo so I can't comment on multichannel DACs).

The Topping DM7+Raspberry Pi is the real winner here IMHO.
You get SOTA balanced 8 Channel DAC, extremely powerful DSP and local file/Airplay/Spotify/Roon streaming for about the same price as a unbalanced Flex here in EU.

 

[Red_Red]

It's actually easier than you think.
You just have to install MoOde or Volumio on the Pi which both come with CamillaDSP build into it.

If you need an optical input you can simply buy a HifimeDIY optical to USB adapter (about 30€) and select input the input source in MoOde.
You can do all the DSP,PEQ and convoution stuff inside camillaDSP and I didn't have any issues running it under MoOde so far (I only used it in stereo so I can't comment on multichannel DACs).

The Topping DM7+Raspberry Pi is the real winner here IMHO.
You get SOTA balanced 8 Channel DAC, extremely powerful DSP and local file/Airplay/Spotify/Roon streaming for about the same price as a unbalanced Flex here in EU.

I know, but on the one hand it's not so obvious for everyone, and on the other hand we lose practicality.

For example, the Flex Eight can be used, for people like me, as a tool for designing passive crossovers for diy speakers. With an RPi running Moode/CamilliaDSP good luck getting to do this in real time and a measurement microphone, and the necessary software, etc. So yes, this is a very special use here.

Otherwise, yes, I understand your point of view. Moreover, once the crossover has been determined with a tool like the flex eight, you can very well use an RPi under camelliadsp to apply it! but the reverse is not really possible if it is not by complicating the task enormously.

 

[juliangst]

I know, but on the one hand it's not so obvious for everyone, and on the other hand we lose practicality.

For example, the Flex Eight can be used, for people like me, as a tool for designing passive crossovers for diy speakers. With an RPi running Moode/CamilliaDSP good luck getting to do this in real time and a measurement microphone, and the necessary software, etc. So yes, this is a very special use here.

Otherwise, yes, I understand your point of view. Moreover, once the crossover has been determined with a tool like the flex eight, you can very well use an RPi under camelliadsp to apply it! but the reverse is not really possible if it is not by complicating the task enormously.

Its as easy as with the Flex. You can access the CamillaDSP Gui over your browser and all filters and crossovers you set get applied instantly. This makes it even easier compared to the Flex because you don't need a physical connection to your PC with the Pi.
Just do measurements with REW from the listening position and export filters to the Pi over the network.

Both the Flex and CamillaDSP require you to do your own measurements and create your own filters and crossovers.
You can upgrade the Flex with Dirac Live but that won't take care of your crossover setup either.

 

[Red_Red]

Maybe I need to take a closer look at this. I'm so used to using the Nanodigi or a sound card that it's possible that I missed what you're talking about. In my mind, this could not be possible because of the latencies between the remote Rpi and the measurement computer preventing, for example, the calculation of the acoustic phasing between the loudspeakers.

 

[juliangst]

Maybe I need to take a closer look at this. I'm so used to using the Nanodigi or a sound card that it's possible that I missed what you're talking about. In my mind, this could not be possible because of the latencies between the remote Rpi and the measurement computer.

It of course depends on the measurement method. If you use sine sweeps it could become a problem or not.
But with pink noise and the RTA method you don’t get any problems.

I might just get this HifiMeDIY optical to USB converter and find out if there really is any delay

 

[Red_Red]

It of course depends on the measurement method. If you use sine sweeps it could become a problem or not.
But with pink noise and the RTA method you don’t get any problems.

I might just get this HifiMeDIY optical to USB converter and find out if there really is any delay

The RTA method makes it possible to correct the faults of the listening room but not to achieve the crossover between several loudspeakers of the same speaker in a neutral environment (outdoor or anechoic). In this case, of course, there is no problem measuring everything remotely as you do. But it's not the same thing at all.

 

[mdsimon2]

Maybe I need to take a closer look at this. I'm so used to using the Nanodigi or a sound card that it's possible that I missed what you're talking about. In my mind, this could not be possible because of the latencies between the remote Rpi and the measurement computer preventing, for example, the calculation of the acoustic phasing between the loudspeakers.

Although a bit more complicated CamillaDSP is definitely a viable option for crossover design. There a few different ways to do it, I probably wouldn't use moode but rather the ubuntu setup documented in my signature as it gives you a bit more flexibility.

With both the Flex and DM7 + CamillaDSP you can only use acoustic timing references as they do not have an analog input for a true loopback with an analog mic. If you are using an audio interface like the MOTU Ultralite Mk5 + CamillaDSP then you have a lot more options as you have an analog input.

In terms of getting a REW signal in to CamillaDSP if you are using a Mac airplay is a viable completely headless option or you can run the RPi in USB gadget mode. Of course if your computer has a SPDIF output (or you have a USB to SPDIF card) and your interface has a SPDIF input like the UL Mk5 or Okto dac8 pro or you add a SPDIF to USB card to your RPi4 with the DM7 that also works.

So lots of options to make it work.

Michael

 

[Red_Red]

Thanks Michael, I had read with great interest your tutorials for using cameliadsp.
You are right to suggest using ubuntu for my use. I need to think a little more about all this because it would require me to change some habits. For the moment there is no hurry, as it is my measurement and "research" system, is quite functional. Also The MOTU Ultralite Mk5+ seems to me the most suitable for the multiple use that I could make of it. On my side I have a Focusrite for the setting for the acoustic phasing (in loopback). You are absolutely right to specify the importance of this and the fact that indeed Flex Eight like the DM7 or the nanodigi that I use do not allow this.

 

[juliangst]

Are there any downsites with using MoOde instead of Ubuntu? I tried both and both are stable and didn’t cause any issues.

MoOde just seems to be more ‚noob friendly‘ and gives you all streaming features and external input support.

I haven’t tried it with multichannel DACs like the topping or Motu though.

 

[MCH]

Are there any downsites with using MoOde instead of Ubuntu? I tried both and both are stable and didn’t cause any issues.

MoOde just seems to be more ‚noob friendly‘ and gives you all streaming features and external input support.

I haven’t tried it with multichannel DACs like the topping or Motu though.

Moode's camilladsp can do multichannel 2 in X out, no problem, see here:

Dummy to dummy multichannel DSP on the ultra cheap instructions

Hello guys, I have been reading and asking here and there about how to set up a multichannel system with DSP on the ultra cheap. And even though many of you helped me a lot to understand the implications and requirements and answer all my stupid questions (special thanks for @mdsimon2 in...

audiosciencereview.com

What do you mean with "external input support"? I thought that was not possible (or very limited) with moode

 

[mdsimon2]

Moode's camilladsp can do multichannel 2 in X out, no problem, see here:

Dummy to dummy multichannel DSP on the ultra cheap instructions

Hello guys, I have been reading and asking here and there about how to set up a multichannel system with DSP on the ultra cheap. And even though many of you helped me a lot to understand the implications and requirements and answer all my stupid questions (special thanks for @mdsimon2 in...

audiosciencereview.com

What do you mean with "external input support"? I thought that was not possible (or very limited) with moode

I haven't tried it but it does seem possible these days -> https://www.bitlab.nl/page_id=1103.

Michael

 

[MCH]

I haven't tried it but it does seem possible these days -> https://www.bitlab.nl/page_id=1103.

Michael

Interesting, thanks!

 

[juliangst]

Moode's camilladsp can do multichannel 2 in X out, no problem, see here:

Dummy to dummy multichannel DSP on the ultra cheap instructions

Hello guys, I have been reading and asking here and there about how to set up a multichannel system with DSP on the ultra cheap. And even though many of you helped me a lot to understand the implications and requirements and answer all my stupid questions (special thanks for @mdsimon2 in...

audiosciencereview.com

What do you mean with "external input support"? I thought that was not possible (or very limited) with moode

Didn’t try it out but MoOde has a menu for input selection. Could work with the Hifimediy or something similar

 

[MCH]

Didn’t try it out but MoOde has a menu for input selection. Could work with the Hifimediy or something similar

Check out what Michael has just posted, maybe it tells you how to do it. This is new for me, besides this, I think that the input selection in Moore only works with two devices, see link below. But please, check it out, this is old information, moode had a couple of updates since that:

Add additional input selection

 

[euge_lee]

Since the clock source of the external data is unknown, the DSP usually has its own clock domain, so there will always be resampling involved. No point in letting Roon do it for you. In fact, it's said that resampling to the same rate may actually be worse than differing sample rates, but I haven't seen any concrete evidence of this.

You are indeed correct... as this is what MiniDSP responded as well.

• All our processors require to resample to the DSP clock rate. Even if it's 96k sample rate, it's a different clock. Does this make sense?
  For that reason the ASRC is always active in all cases. It won't make a difference indeed. Our SRC is indeed the same in all case and won't be that different from what Roon does since it's an HARDWARE ASRC on the chipset already optimized for best performance.

 

[DWPress]

All our processors require to resample to the DSP clock rate.

This has been true with miniDSP products for a long time, my old 4x10 processed everything in 24/96 a decade ago. Still best to feed these things with a digital signal to avoid the ADC stage. The good news is even the 4x10 was measured back then and even if not SOTA all concerns were still at or below audible thresholds.

@Red_Red - I use my system to create and measure crossovers/filters for my speakers as well. Not quite as cheap as going with Camilla DSP but maybe more flexible for your needs and another way of going about it using software and audio plugins is linked in my signature. I have a usb Umik mic and analog ones I've used with a pre and loopback but will often just use acoustic timing reference in the wav sweep file through whatever app I'm using for music playback rather than directly in REW.

Lots of ways to break free of the miniDSP ecosystem and its limitations but I do think the Flex is a pretty good piece of kit if it suits ones needs. There will always be more flexibility and control in a multi ch DAC + computer running the show.

 

[amper42]

This has been true with miniDSP products for a long time, my old 4x10 processed everything in 24/96 a decade ago. Still best to feed these things with a digital signal to avoid the ADC stage. The good news is even the 4x10 was measured back then and even if not SOTA all concerns were still at or below audible thresholds.

@Red_Red - I use my system to create and measure crossovers/filters for my speakers as well. Not quite as cheap as going with Camilla DSP but maybe more flexible for your needs and another way of going about it using software and audio plugins is linked in my signature. I have a usb Umik mic and analog ones I've used with a pre and loopback but will often just use acoustic timing reference in the wav sweep file through whatever app I'm using for music playback rather than directly in REW.

Lots of ways to break free of the miniDSP ecosystem and its limitations but I do think the Flex is a pretty good piece of kit if it suits ones needs. There will always be more flexibility and control in a multi ch DAC + computer running the show.

One annoying FLEX issue is if I accidentally try to play a Qobuz file with a resolution of 96Hz or higher most of the time I just get static in the speakers. 44Khz files work fine but lots of HiRes Qobuz files won't play. That issue disappears when I switch in the RME ADI-2 or the D90SE DAC.

 

[euge_lee]

This has been true with miniDSP products for a long time, my old 4x10 processed everything in 24/96 a decade ago. Still best to feed these things with a digital signal to avoid the ADC stage. The good news is even the 4x10 was measured back then and even if not SOTA all concerns were still at or below audible thresholds.

I'm actually a dummy... I used to use a 2x4 HD and SMSL DAC feeding it analog... but recently got the FLEX and am sending it USB and using it as my DAC... so it was somewhat moot to begin with since I was bypassing ADC... but I know it still wants to upsample to 96kHz for DSP... which is fine and I'll let it do its thing.

 

[will.b]

One annoying FLEX issue is if I accidentally try to play a Qobuz file with a resolution of 96Hz or higher most of the time I just get static in the speakers. 44Khz files work fine but lots of HiRes Qobuz files won't play. That issue disappears when I switch in the RME ADI-2 or the D90SE DAC.

I've experienced the same when the audio output is set to Wasapi(Exclusive Mode) in Qobuz.
Change it to normal Wasapi and it's fine.
Works fine with either mode via Roon.